1. Field of the Invention
The present invention relates to a high-frequency diode oscillator which is a high-frequency oscillator such as a Gunn diode oscillator built in, for example, a high-frequency circuit such as a millimeter-wave integrated circuit and in which a nonradiative dielectric waveguide is used, and also relates to a millimeter-wave transmitting/receiving apparatus equipped with this high-frequency diode oscillator.
2. Description of the Related Art
A conventional Gunn diode oscillator is shown in FIG. 31. In FIG. 31, reference numeral 201 denotes a pair of parallel plate conductors. By setting an interval z between the conductors to zxe2x89xa6xcex/2, a so-called nonradiative dielectric waveguide (referred to as an NRD guide, hereafter) is configured, which prevents noise from entering from outside into a dielectric strip 207 and prevent s high-frequency signals from radiating outside, thereby transmitting signals. Herein, xcex represents the wavelength of an electromagnetic wave (high-frequency signal) which propagates in the air at a used frequency.
Further, reference numeral 202 denotes a nearly rectangular parallelepiped metal member such as a metal block for mounting a Gunn diode device, reference numeral 203 denotes a Gunn diode device which is a kind of microwave diodes for oscillating microwaves, reference numeral 204 denotes a wiring board which is mounted on one side surface of the metal member 202 and which is provided with a choke-type bias supply strip 204a for supplying a bias voltage to the Gunn diode device 203 and functioning as a low-pass filter for preventing leakage of high-frequency signals, reference numeral 205 denotes a strip conductor such as a metal foil ribbon which connects the choke-type bias supply strip 204a and the upper conductor of the Gunn diode device 203, reference numeral 206 denotes a metal strip resonator which is made by disposing a resonating metal strip line 206a to a dielectric base, and reference numeral 207 denotes a dielectric strip which transmits high-frequency signals resonated by the metal strip resonator 206 to the outside. In FIG. 31, the upper one of the parallel plate conductors 201 is partially cut away in order to show the interior thereof.
In the NRD guide type of Gunn diode oscillator of FIG. 31, the metal member 202 mounted with the Gunn diode device 203 is disposed between the pair of parallel plate conductors 201. High-frequency signals (electromagnetic waves) such as microwaves oscillated from the Gunn diode device 203 are led out to the dielectric strip 207 via the metal strip resonator 206 having the metal strip line 206a. 
Then, in the choke-type bias supply strip 204a, a choke in which the spatial cycle (length of one) of wide strips and the spatial cycle (length of one) of narrow strips are repeated by a cycle of approximately xcex/4, respectively, is formed as shown in FIG. 32. Further, the length of the strip conductor 205 is also set to approximately xcex/4, and the strip conductor 205 functions as part of a low-pass filter.
However, the conventional Gunn diode oscillator is configured so that the metal strip resonator 206, the metal member 202 for mounting the Gunn diode device 203, and the dielectric strip 207 are registered individually and interposed between the parallel plate conductors 201, 201. For this reason, the position of the metal strip resonator 206 varies due to vibration and its weight in the case where the processing accuracy of the metal strip resonator 206 is low, and propagation characteristics to the dielectric strip 207 Is deteriorated in the case where the resonator is not accurately registered. That is to say, the conventional Gunn diode oscillator has a problem that the processing accuracy and positioning accuracy of the metal strip resonator 206 need to be controlled, workability in production is bad, and therefore the oscillator is not suitable for mass production.
In FIGS. 31 and 32, the strip 204a of the wiring board 204 is diagonally shaded so that the configuration is clearly shown. This is true in other drawings attached to the specification of this application.
FIG. 33 is a partially cutaway view in perspective of another prior art. This prior art of FIG. 33 is similar to the prior art as shown in FIGS. 31 and 32, and like elements will be denoted by like reference numerals. A dielectric strip 207 disposed in the vicinity of a Gunn diode 203 has a function of receiving high-frequency signals and propagating outside. A strip conductor 205 is spanned between a choke-type bias supply strip 204a and the Gunn diode 203 spaced at a predetermined interval from the surface of a metal member 202. A square-pole-like dielectric chip 308 is disposed close to a strip conductor 205 to be electromagnetically connected thereto, whereby it is made possible to control the oscillation frequency of high-frequency signals.
The prior art as shown in FIG. 33 also has the same problem as the prior art as shown in FIGS. 31 and 32.
FIG. 34 is a partially cutaway view in perspective of still another prior art, and FIG. 35 is a perspective view showing the configuration of part of the prior art as shown in FIG. 34. This prior art as shown in FIGS. 34 and 35 is similar to the prior arts as shown in FIGS. 31-33, and like elements will be denoted by like reference numerals. In specific, in the prior art of FIGS. 34 and 35, a wiring board 208 provided with a varactor diode 210 which is a frequency modulating diode and a kind of variable capacitance diode is mounted on a mid-portion of a dielectric strip 207. A bias voltage applying direction B of the varactor diode 210 is set to a direction which is perpendicular to a propagation direction D of high-frequency signals in the dielectric strip 207 and parallel to the main surfaces of parallel plate conductors 201. The bias voltage applying direction B coincides with an electric field direction E of LSM01 mode of high-frequency signals which propagate in the dielectric strip 207. With this, by electromagnetically coupling high-frequency signals and the varactor diode 210 and controlling a bias voltage to change the capacitance of the varactor diode 210, it is possible to control the oscillation frequency of high-frequency signals. Further, reference numeral 209 denotes a dielectric plate with high relative dielectric constant for matching the impedance of the varactor diode 210 and that of the dielectric strip 207. In FIG. 34, the upper one of the parallel plate conductors 201 is partially cut away in order to show the interior thereof.
Further, as shown in FIG. 35, a second choke-type bias supply strip 212 is formed on one main surface of the wiring board 208, and a beam lead type of varactor diode 210 is disposed on a mid-portion of the second choke-type bias supply strip 212. At a connecting portion of the second choke-type bias supply strip 212 to the varactor diode 210, an electrode 211 is formed.
Then, high-frequency signals oscillated from a Gunn diode 203 are led out to the dielectric strip 207 through a metal strip resonator 206. Subsequently, the high-frequency signals are partially reflected at the varactor diode 210, and return toward the Gunn diode 203. As the reflection signals change together with the capacitance of the varactor diode 210, the oscillation frequency changes.
In the choke-type bias supply strip 204a, wide strips and narrow strips are alternately formed to construct a choke in which the length of one wide strip and the length of one narrow strip are approximately xcex/4, respectively. Further, the length of a strip conductor 205 is also set to approximately xcex/4, and the strip conductor 205 functions as part of a low-pass filter.
However, this conventional Gunn diode oscillator is configured so that high-frequency signals pass through the wiring board 208 mounted with the varactor diode 210, and therefore has such a problem that the output of high-frequency signals decreases. Further, although it is necessary to change the insertion position of the varactor diode 210 in order to regulate the frequency modulation width of high-frequency signals, it is difficult to control the frequency modulation width by regulating the position. Therefore, the frequency modulation width cannot be controlled with ease.
Therefore, the present invention was completed in view of the above circumstances, and an object of the invention is to provide a high-frequency diode oscillator in which difficulty in processing and positioning of parts can be lowered, namely, processing accuracy and positioning accuracy can be easily controlled, and excellent workability in production and assembly can be achieved.
The invention was completed in view of the above circumstances, and another object of the invention is to provide a downsized high-frequency diode oscillator in which by disposing a frequency regulating member made of a dielectric or metal so that fine adjustment of position is carried out with ease and high reproducibility, fine-regulation of oscillation frequency can be achieved with high reproducibility, and the fine adjustment of position can be achieved by downsizing the frequency regulating member.
The invention was completed in view of the above circumstances, and still another object of the invention is to provide a high-frequency diode oscillator in which high-power high-frequency signals can be obtained and control of frequency modulation width can be carried out with ease.
Still another object of the invention is to provide a millimeter-wave transmitting/receiving apparatus equipped with a high-frequency diode oscillator in the above mentioned objects are achieved.
The invention provides a high-frequency diode oscillator comprising:
a metal member which is disposed between parallel plate conductors disposed at an interval equal to or less than one half of wavelength xcex of a high-frequency signal,
the metal member being provided with a high-frequency diode which oscillates a high-frequency signal,
a choke-type bias supply strip comprising wide strips and narrow strips which are alternately arranged, and
a strip conductor for linearly connecting the choke-type bias supply strip to the high-frequency diode; and
a dielectric strip for receiving and propagating the high-frequency signal, which is disposed in a vicinity of the high-frequency diode between the parallel plate conductors,
length of the strip conductor being set to approximately {(3/4)+n}xcex (n represents an integer of 0 or more), and
length of the wide strips and narrow strips of the choke-type bias supply strip being set to approximately xcex/4.
In the high-frequency diode oscillator of the invention it is preferable that a dielectric chip having a main surface opposed to a main surface of the strip conductor is disposed in proximity to the strip conductor to be electromagnetically coupled thereto.
In the high-frequency diode oscillator of the invention it is preferable that length of the strip conductor is within a range of approximately 3xcex/4 to approximately {(3/4)+3}xcex.
In the high-frequency diode oscillator of the invention it is preferable that length of the strip conductor is within a range of {(3/4)+n}xcexxc2x120%.
In the high-frequency diode oscillator of the invention it is preferable that the choke-type bias supply strip and the strip conductor are made of Cu, Al, Au, Ag, W, Ti, Ni, Cr, Pd or Pt.
In the high-frequency diode oscillator of the invention it is preferable that the dielectric strip and the dielectric chip are made of cordierite ceramics or alumina ceramics.
In the high-frequency diode oscillator of the invention it is preferable that an interval between the main surface of the dielectric chip and the main surface of the strip conductor is in a range of 0.1 to 1.0 mm.
According to the invention, with such configurations, the choke-type bias supply strip and the strip conductor function as a resonator which determines the oscillation frequency of the high-frequency diode, so that an extra resonator such as a metal strip resonator is unnecessary. Therefore, the metal member for mounting the high-frequency diode and the dielectric strip is easily positioned, whereby workability in production is largely improved. Further, the invention has such an effect that a loss due to a separate resonator such as a metal strip resonator is avoided and excellent propagation characteristics of high-frequency signals can be obtained.
According to the invention, it is preferable that a dielectric strip having a main surface opposed to a main surface of the strip conductor is disposed in proximity to the strip conductor to be electromagnetically coupled thereto. With this, regulation of oscillation frequency of the high-frequency diode oscillator is further facilitated, and mass-productivity is further increased.
According to the invention, the cycle of the wide strips and narrow strips of the choke-type bias supply strip is set to approximately xcex/4 and the length of the strip conductor is set to approximately {(3/4)+n}xcex (n represents an integer of 0 or more). With this, the choke-type bias supply strip and the strip conductor function as a resonator which determines the oscillation frequency of the high-frequency diode, so that an extra resonator such as a metal strip resonator is unnecessary. Therefore, positioning of the metal member for mounting the high-frequency diode and the dielectric strip is remarkably facilitated, whereby oscillation characteristics are controlled and increased with ease, and workability in production is largely increased. Further, the invention has such an effect that a loss due to a separate resonator such as a metal strip resonator is avoided and improved propagation characteristics of high-frequency signals are obtained.
In the high-frequency diode oscillator of the invention it is preferable that the metal member has a hole formed at a position corresponding to the strip conductor, and a column-like frequency regulating member which is inserted into the hole and disposed in proximity to the strip conductor so that an end thereof protrudes from a surface of the metal member.
In the high-frequency diode oscillator of the invention it is preferable that the frequency regulating member is made of cordierite ceramics, alumina ceramics, Cu, Al, Fe or stainless steel.
In the high-frequency diode oscillator of the invention it is preferable that an interval between the frequency regulating member and the strip conductor is in a range of 0.05 to 0.10 mm.
In the high-frequency diode oscillator of the invention it is preferable that an area of an end surface of the frequency regulating member opposed to the strip conductor is in a range of 0.10 to 2.0 mm2.
According to the invention, with such configurations, the choke-type bias supply strip and the strip conductor function as a resonator which determines the oscillation frequency of the high-frequency diode. When the frequency regulating member is disposed in proximity to the strip conductor of the resonator to be electromagnetically coupled thereto, the position of the frequency regulating member can be finely regulated with ease and reproducibility. Therefore, the invention has such an effect that the substantial resonator length of the resonator can be finely regulated and, as a result, the oscillation frequency can be finely regulated with reproducibility. Further, by downsizing the frequency regulating member and enabling fine regulation of the position, the high-frequency diode oscillator is downsized as a whole.
According to the invention, the cycles of the wide strips and narrow strips of the choke-type bias supply strip are set to approximately xcex/4, respectively, the length of the strip conductor is set to approximately {(3/4)+n}xcex (n represents an integer of 0 or more), and the metal member has a hole formed at a position corresponding to the strip conductor and a column-like frequency regulating member inserted into the hole and disposed in proximity to the strip conductor so that the end thereof protrudes from the surface of the metal member. With this, the choke-type bias supply strip and the strip conductor function as a resonator which determines the oscillation frequency of the high-frequency diode. When the frequency regulating member is disposed in proximity to the strip conductor of the resonator to be electromagnetically coupled thereto, the position of the frequency regulating member can be finely regulated with ease and reproducibility. Therefore, the substantial resonator length of the resonator can be finely regulated and, as a result, the oscillation frequency can be finely regulated with reproducibility. Further, by downsizing the frequency regulating member and enabling fine regulation of the position, the high-frequency diode oscillator is downsized as a whole.
In the high-frequency diode oscillator of the invention it is preferable that a frequency modulating diode whose bias voltage applying direction is set to a direction parallel to an electric field generated at the strip conductor is disposed in proximity to the strip conductor to be electromagnetically coupled thereto.
According to the invention, with such a configuration, the choke-type bias supply strip and the strip conductor function as a resonator which determines the oscillation frequency of the high-frequency diode. By disposing a modulation circuit board provided with the frequency modulating diode, in proximity to the strip conductor of the resonator to be electromagnetically coupled with the strip conductor, and changing a bias voltage applied to the frequency modulating diode, it is possible to control the oscillation frequency. Further, since there is no need to place a frequency modulating diode in the dielectric strip, it is possible to obtain a high output with low loss and downsize the oscillator as a whole. Furthermore, by regulating the position of the frequency modulating diode, it is possible to change the strength of electromagnetic coupling between the strip conductor which also functions as a resonator and the frequency modulating diode, and thereby regulate the frequency modulation width.
According to the invention, the lengths of the wide strips and narrow strips of the choke-type bias supply strip are set to approximately xcex/4, respectively, the length of the strip conductor is set to approximately {(3/4)+n}xcex (n represents an integer of 0 or more), and a frequency modulating diode whose bias voltage applying direction is set to a direction parallel to an electric field generated at the strip conductor is disposed in proximity to the strip conductor to be electromagnetically coupled thereto. With this, the choke-type bias supply strip and the strip conductor function as a resonator which determines the oscillation frequency of the high-frequency diode. By disposing a modulation circuit board provided with the frequency modulating diode, in proximity to the strip conductor of the resonator to be electromagnetically coupled thereto, and changing a bias voltage applied to the frequency modulating diode, it is possible to control the oscillation frequency. Further, since there is no need to dispose a frequency modulating diode in the dielectric strip as in the case of a conventional oscillator, it is possible to obtain a high output with low loss and downsize the oscillator as a whole. Furthermore, by regulating the position of the frequency modulating diode, it is possible to change the strength of electromagnetic coupling between the strip conductor and the frequency modulating diode, and thereby regulate the frequency modulation width.
In the high-frequency diode oscillator of the invention it is preferable that the frequency modulating diode is mounted on a modulation circuit board composed of a wiring board having a main surface perpendicular to the parallel plate conductors on which main surface a second choke-type bias supply strip is formed, and an auxiliary board which stands on a mid-portion of the second choke-type bias supply strip and has a main surface on which a connection conductor connected to the second choke-type bias supply strip is formed, and the frequency modulating diode is connected to a mid-portion of the connection conductor on the auxiliary board.
In the high-frequency diode oscillator of the invention it is preferable that an interval between the frequency modulating diode and the strip conductor is set to the wavelength xcex or less.
In the high-frequency diode oscillator of the invention it is preferable that a position of the frequency modulating diode with respect to the strip conductor is within a range of one quarter the length of the strip conductor toward the high-frequency diode or choke-type bias supply strip from a center of the strip conductor.
According to the invention, preferably the frequency modulating diode is mounted on a modulation circuit board composed of a wiring board having the main surface perpendicular to the parallel plate conductors, on which main surface a second choke-type bias supply strip is formed, and an auxiliary board which stands on the mid-portion of the second choke-type bias supply strip and has the main surface on which a connection conductor connected to the second choke-type bias supply strip is formed, and the frequency modulating diode is connected to the mid-portion of the connection conductor on the auxiliary board. With this, the shape of the modulation circuit board seen from the top becomes a convex, so that displacement, twist or the like is decreased and stability in mounting is remarkably improved. Further, since it is possible to displace the frequency modulating diode in proximity to the strip conductor and regulate the position thereof in a state where a bias voltage applying direction of the frequency modulating diode coincides with an electric field direction of high-frequency signals, it is possible to regulate the frequency modulation width with ease.
With the above configuration, the shape of the modulation circuit board seen from the top becomes a convex, so that displacement, twist or the like is decreased and stability of mount is exceedingly increased. Further, since it is possible to dispose the frequency modulating diode in proximity to the strip conductor and regulate the position thereof in a state where a bias voltage applying direction of the frequency modulating diode coincides with an electric field direction of high-frequency signals, it is possible to regulate the frequency modulation width with ease.
Further, it is preferable that the interval between the frequency modulating diode and the strip conductor is set to the wavelength xcex or less. By regulating the interval within the above range, it is possible to increase the output of high-frequency signals and broaden the frequency modulation width.
In the high-frequency diode oscillator of the invention it is preferable that a through hole is formed in the vicinity of the strip conductor on at least one of the parallel plate conductors, and a column-like frequency regulating member which is protruded from a surface of one of the parallel plate conductors which surface confronts a surface of the other of the parallel plate conductors to be electromagnetically coupled thereto is disposed in the through hole.
In the high-frequency diode oscillator of the invention it is preferable that a distance between the frequency regulating member and the strip conductor is one half of the wavelength xcex or less.
In the high-frequency diode oscillator of the invention it is preferable that a shape of the protrusion of the frequency regulating member is tapered.
In the high-frequency diode oscillator of the invention it is preferable that the frequency regulating member is made of cordierite ceramics, alumina ceramics, Cu, Al, Fe or stainless steel.
In the high-frequency diode oscillator of the invention it is preferable that an area of a surface of the frequency regulating member opposed to the strip conductor is in a range of 0.5 to 3.0 mm2.
According to the invention, with such configurations, the choke-type bias supply strip and the strip conductor function as a resonator which determines the oscillation frequency of the high-frequency diode. When the frequency regulating member is disposed in proximity to the strip conductor of the resonator to be electromagnetically coupled to the conductor, the position of the frequency regulating member can be finely regulated with ease and reproducibility. Therefore, the invention has such an effect that the substantial resonator length of the resonator can be finely regulated and, as a result, the oscillation frequency can be finely regulated with reproducibility. Further, by downsizing the frequency regulating member and enabling fine regulation of the position, the high-frequency diode oscillator is downsized as a whole.
According to the invention, in the NRD guide type of high-frequency diode oscillator, the lengths of the wide strips and narrow strips of the choke-type bias supply strip are set to approximately xcex/4, respectively, the length of the strip conductor is set to approximately {(3/4)+n}xcex (n represents an integer of 0 or more), a throughhole is formed in the vicinity of the strip conductor on at least one of the parallel plate conductors, and a column-like frequency regulating member which is protruded from a surface of one of the parallel plate conductors which surface confronts a surface of the other of the parallel plate conductors to be electromagnetically coupled thereto is disposed in the through hole. With this, the choke-type bias supply strip and the strip conductor function as a resonator which determines the oscillation frequency of the high-frequency diode. When the frequency regulating member is disposed in proximity to the strip conductor of the resonator to be electromagnetically coupled thereto, the position of the frequency regulating member can be finely regulated with ease and reproducibility. Therefore, the substantial resonator length of the resonator can be finely regulated and, as a result, the oscillation frequency can be finely regulated with reproducibility. Further, by downsizing the frequency regulating member and enabling fine regulation of the position, the high-frequency diode oscillator is downsized as a whole.
According to the invention, it is preferable that the distance between the frequency regulating member and the strip conductor is xcex/2 or less. With this, the frequency regulating member and the strip conductor are electromagnetically coupled to each other in a preferable manner. By finely regulating the degree of electromagnetic coupling in such a state, it is possible to finely regulate the substantial resonator length of the resonator.
As shown in FIGS. 14-18, the invention provides a millimeter-wave transmitting/receiving apparatus comprising the following parts disposed between parallel plate conductors disposed at an interval equal to or less than one half of wavelength of transmission millimeter-wave signals.
(a) A high-frequency diode oscillator for outputting millimeter-wave signals, including:
a metal member on which a high-frequency diode for oscillating high-frequency signals, a choke-type bias supply strip for supplying a bias voltage to the high-frequency diode, the choke-type bias supply strip comprising wide strips and narrow strips which are alternately arranged, and a strip conductor for linearly connecting the choke-type bias supply strip and the high-frequency diode are disposed; and
a dielectric strip disposed in a vicinity of the high-frequency diode, for receiving and propagating the millimeter-wave signals,
lengths of the wide strips and narrow strips of the choke-type bias supply strip being set to approximately xcex/4 (xcex represents a wavelength of a high-frequency signal), respectively, and a length of the strip conductor being set to approximately {(3/4)+n}xcex (n represents an integer of 0 or more).
(b) A first dielectric strip having one end where the high-frequency diode is disposed, for propagating a millimeter-wave signal outputted from the high-frequency diode oscillator.
(c) A variable capacitance diode disposed so that a bias voltage applying direction coincides with an electric field direction of the millimeter-wave signal, for periodically controlling a bias voltage and thereby outputting the millimeter-wave signal as a frequency-modulated transmission millimeter-wave signal.
(d) A second dielectric strip having one end which is disposed in proximity to or joined to a portion of the first dielectric strip on a downstream side from the variable capacitance diode in a transmitting direction of the transmission millimeter-wave signal, so as to be electromagnetically coupled with the portion.
(e) A circulator having an input end, an input/output end and an output end,
the other end of the first dielectric strip being coupled with the input end,
a transmission millimeter-wave signal inputted to the input end being outputted to the input/output end,
a reception signal inputted to the input/output end being outputted to the output end.
(f) A third dielectric strip having one end which is coupled to the input/output end of the circulator, and another end where a transmission/reception antenna is disposed.
(g) A fourth dielectric strip having one end which is coupled with the output end of the circulator.
(h) A mixer for mixing signals transmitted to the second and fourth dielectric strips, and generating intermediate-frequency signals by disposing in proximity to each other or joining a mid-portion of the second dielectric strip and a mid-portion of the fourth dielectric strip so as to be electromagnetically coupled to each other.
The invention provides a millimeter-wave transmitting/receiving apparatus comprising the following parts disposed between parallel plate conductors disposed at an interval equal to or less than one half of wavelength of transmission millimeter-wave signals.
(a) A high-frequency diode oscillator for outputting millimeter-wave signals, including:
a metal member on which a high-frequency diode for oscillating high-frequency signals, a choke-type bias supply strip for supplying a bias voltage to the high-frequency diode, the choke-type bias supply strip comprising wide strips and narrow strips which are alternately arranged, and a strip conductor for linearly connecting the choke-type bias supply strip and the high-frequency diode are disposed; and
a dielectric strip disposed in a vicinity of the high-frequency diode, for receiving and propagating the millimeter-wave signals,
lengths of the wide strips and narrow strips of the choke-type bias supply strip being set to approximately xcex/4 (xcex represents a wavelength of a high-frequency signal), respectively, and a length of the strip conductor being set to approximately {(3/4)+n}xcex (n represents an integer of 0 or more).
(b) A first dielectric strip having one end where the high-frequency diode is disposed, for propagating a millimeter-wave signal outputted from the high-frequency diode oscillator.
(c) A pulse modulation diode disposed to be interposed in or attached to the first dielectric strip so that a bias voltage applying direction coincides with an electric field direction of the millimeter-wave signal, for outputting a transmission millimeter-wave signal obtained by pulse-modulating the millimeter-wave, by on-off of a bias voltage.
(d) A second dielectric strip having one end which is disposed in proximity to or joined to a portion of the first dielectric strip on an upstream side from the pulse modulation diode in a transmitting direction of the transmission millimeter-wave signal, so as to be electromagnetically coupled with the portion.
(e) A circulator having an input end, an input/output end and an output end,
the other end of the first dielectric strip being coupled with the input end,
a transmission millimeter-wave signal inputted to the input end being outputted to the input/output end,
a reception signal inputted to the input/output end being outputted to the output end.
(f) A third dielectric strip having one end which is coupled to the input/output end of the circulator, and another end where a transmission/reception antenna is disposed.
(g) A fourth dielectric strip having one end which is coupled with the output end of the circulator.
(h) A mixer for mixing signals transmitted to the second and fourth dielectric strips, and generating intermediate-frequency signals by disposing in proximity to each other or joining a mid-portion of the second dielectric strip and a mid-portion of the fourth dielectric strip so as to be electromagnetically coupled to each other.
The invention provides a millimeter-wave transmitting/receiving apparatus comprising the following parts disposed between parallel plate conductors disposed at an interval equal to or less than one half of wavelength of transmission millimeter-wave signals.
(a) A high-frequency diode oscillator for outputting millimeter-wave signals, including:
a metal member on which a high-frequency diode for oscillating high-frequency signals, a choke-type bias supply strip for supplying a bias voltage to the high-frequency diode, the choke-type bias supply strip comprising wide strips and narrow strips which are alternately arranged, and a strip conductor for linearly connecting the choke-type bias supply strip and the high-frequency diode are disposed; and
a dielectric strip disposed in a vicinity of the high-frequency diode, for receiving and propagating the millimeter-wave signals,
lengths of the wide strips and narrow strips of the choke-type bias supply strip being set to approximately xcex/4 (xcex represents a wavelength of a high-frequency signal), respectively, and a length of the strip conductor being set to approximately {(3/4)+n}xcex (n represents an integer of 0 or more).
(b) A first dielectric strip having one end where the high-frequency diode is disposed, for propagating a millimeter-wave signal outputted from the high-frequency diode oscillator.
(c) A variable capacitance diode disposed so that a bias voltage applying direction coincides with an electric field direction of the millimeter-wave signal, for periodically controlling a bias voltage and thereby outputting the millimeter-wave signal as a frequency-modulated transmission millimeter-wave signal.
(d) A second dielectric strip having one end which is disposed in proximity to or joined to a portion of the first dielectric strip on a downstream side from the variable capacitance diode in a transmitting direction of the transmission millimeter-wave signal, so as to be electromagnetically coupled with the portion.
(e) A circulator having an input end, an input/output end and an output end,
the other end of the first dielectric strip being coupled with the input end,
a transmission millimeter-wave signal inputted to the input end being outputted to the input/output end,
a reception signal inputted to the input/output end being outputted to the output end.
(f) A third dielectric strip having one end which is coupled to the input/output end of the circulator, and another end where a transmission antenna is disposed.
(g) A terminator coupled to the output end of the circulator.
(h) A fourth dielectric strip having one end where a reception antenna is disposed, for guiding a received millimeter-wave signal.
(i) A mixer for mixing signals transmitted to the second and fourth dielectric strips, and generating intermediate-frequency signals by disposing in proximity to each other or joining a mid-portion of the second dielectric strip and a mid-portion of the fourth dielectric strip so as to be electromagnetically coupled to each other.
The invention provides a millimeter-wave transmitting/receiving apparatus comprising the following parts disposed between parallel plate conductors disposed at an interval equal to or less than one half of wavelength of transmission millimeter-wave signals.
(a) A high-frequency diode oscillator for outputting millimeter-wave signals, including:
a metal member on which a high-frequency diode for oscillating high-frequency signals, a choke-type bias supply strip for supplying a bias voltage to the high-frequency diode, the choke-type bias supply strip comprising wide strips and narrow strips which are alternately arranged, and a strip conductor for linearly connecting the choke-type bias supply strip and the high-frequency diode are disposed; and
a dielectric strip disposed in a vicinity of the high-frequency diode, for receiving and propagating the millimeter-wave signals,
lengths of the wide strips and narrow strips of the choke-type bias supply strip being set to approximately xcex/4 (xcex represents a wavelength of a high-frequency signal), respectively, and a length of the strip conductor being set to approximately {(3/4)+n}xcex (n represents an integer of 0 or more).
(b) A first dielectric strip having one end where the high-frequency diode is disposed, for propagating a millimeter-wave signal outputted from the high-frequency diode oscillator.
(c) A pulse modulation diode disposed to be interposed in or attached to the first dielectric strip so that a bias voltage applying direction coincides with an electric field direction of the millimeter-wave signal, for outputting a transmission millimeter-wave signal obtained by pulse-modulating the millimeter-wave, by on-off of a bias voltage.
(d) A second dielectric strip having one end which is disposed in proximity to or joined to a portion of the first dielectric strip on an upstream side from the pulse modulation diode in a transmitting direction of the transmission millimeter-wave signal, so as to be electromagnetically coupled with the portion.
(e) A circulator having an input end, an input/output end and an output end,
the other end of the first dielectric strip being coupled with the input end,
a transmission millimeter-wave signal inputted to the input end being outputted to the input/output end,
a reception signal inputted to the input/output end being outputted to the output end.
(f) A third dielectric strip having one end which is coupled to the input/output end of the circulator, and another end where a transmission antenna is disposed.
(g) A terminator coupled to the output end of the circulator.
(h) A fourth dielectric strip having one end where a reception antenna is disposed, for guiding a received millimeter-wave signal.
(i) A mixer for mixing signals transmitted to the second and fourth dielectric strips, and generating intermediate-frequency signals by disposing in proximity to each other or joining a mid-portion of the second dielectric strip and a mid-portion of the fourth dielectric strip so as to be electromagnetically coupled to each other.